Development and characterization of ketorolac tromethamine osmotic pump tablets

The aim of the present study was to prepare and evaluate elementary osmotic pump tablets (OPT) of ketorolac tromethamine (KT). Because of its high potency, short half-life and excellent water solubility it would appear to be the drug of choice for these formulations. Twenty OPT formulae were prepared and subjected to release-rate study and the release data were analyzed to determine the drug release order. Compatibility study between KT and the used excipients was carried out also scanning electron microscopy in order to elucidate the microporous nature of the tablet surfaces. The effects of an increase in weight, agitation intensity, pH and type of coating polymer on drug release from the optimal formulation (OPT-19) were studied. It was found that the optimal OPT formula was able to deliver KT at a zero-order for up to 12 h independent of both release media and agitation rates: the effect of type of coating polymer was not significant.